A problem with lighted instrument panels in vehicles such as automobiles lies in the fact that light is emitted from such instrument panels through a wide range of angles. Some of this light will strike glass surfaces such as the windshield and be reflected back to the driver. While sunlight prevents such reflections from being visible during the day, they are often clearly visible during the night. Such reflections can create a dangerous situation by distracting the driver or even obscuring the driver's view.
One method of preventing such reflections is to use louvered plastic films in the window covering the instrument panel. The louvers partially collimate the light allowing the driver to read the instruments, but preventing the light from reaching the windshield to create reflections. Such films are often called "light-collimating films" although they actually only provide partial collimation. This can be a very effective system for controlling such reflections. A problem arises when there is printing on the film, however. Of the inks typically used for printing on such films, only black is truly opaque. Other colors will transmit some light. The light that is transmitted will be scattered, defeating the purpose of the collimating film. Thus a system for providing lettering on such louvered plastic films without scattering the light transmitted therethrough is desirable.